Watches of this type have been known for several centuries now. First of all, the winding stem was generally accessible through an aperture made in the watch dial for winding the movement. Prior to generalisation of watch crystals, the dial was typically protected by a cover to avoid damaging the hands or interfering with the working thereof when the watch was arranged in the user's pocket. Consequently, the inside of the watch case was capable of communicating with the external environment through the winding aperture, the movement also being protected by the same cover. Thereafter, since the use of watch crystals became common, watch movements were adapted to arrange the aperture in different area of the watch case from the dial, namely behind the case. Since this aperture exposing the interior of the watch case to the external environment was detrimental to the watch movement, it became common to install a cover to protect the back of the case, particularly the aperture allowing free access to the winding stem. New watch movement structures emerged later, which were wound using a winding stem-crown integrated in the watch. Such movements advantageously allow the movement to be wound without using a specific tool for this purpose, namely a winding key. Moreover, such movements allow the watch case to be completely closed and thus the watch movement to be protected from the external environment.
However, these days, certain watchmakers now wish to uphold the old tradition of pocket watches of the type that are wound with a key, these watches generally being for the top end of the market and made of gold. In such case, the fact of having a cover on the back of the watch case has a certain number of drawbacks. In fact, the construction of the case is not only more complex, particularly because of the hinge which is necessary to hold the cover on, but also more expensive because of the quantity of material required to make the cover. Moreover, certain watchmakers wish to design replicas of old watches, certain of which have an access to the winding stem on the back face without having a cover, these replicas advantageously respecting current manufacturing quality standards. In such case the watch movements are significantly exposed as regards the risk of dust penetrating the interior of the watch case.